Wet fractionation of forage to reduce energy requirements of dehydration. Final technical report, August 12, 1978-April 30, 1982
Wet processing fractionates fresh alfalfa into leaf protein concentrate (LPC), alfalfa solubles, and press cake products. The process can reduce energy consumption compared to normal dehydration of freshly chopped alfalfa by recovering sensible and latent heat from the dryer exhaust gases using a gas recycle system and waste heat evaporator, and by reducing the water evaporated per ton of product produced. A conventional commercial alfalfa dehydration plant (Valley Dehydrating Company, Sterling Co; VDC) was modified to an LPC operation with a design capacity of 30 tons of chopped alfalfa per hour. During the experimental period the plant operated at 15 to 24 tons/h, and produced an average LPC yield of 12.8% (dry basis). The VDC plant consumed 25% less total energy (29% less natural gas; 108% more electrical energy) than that estimated for conventional dehydration of chopped alfalfa. Energy savings were lower than anticipated because of inefficiencies resulting from plant operation at less than design capacity. Based on the experience at VDC, future LPC plants are projected to reduce overall energy consumption by 35% (39% less natural gas; 63% more electrical energy) as compared to conventional dehydration. The VDC products were marketed readily; the press cake was sold to cattle feeders at a price equivalent to dehydrated alfalfa, and the LPC to a broiler producer at prices varying from $430 to $590/ton. Animal performance trials using VDC produced products were highly satisfactory. Projected current cost of a new LPC plant processing 40 tons of chopped alfalfa per hour is 4.7 million dollars; the cost of converting an existing 20 ton/h dehydration plant to a 40 ton/h LPC plant is estimated at 3.6 million dollars. The calculated rate of return on investment for the new plant was 12.0, 26.2 and 40.4% for operating seasons of 130, 180 and 230 days, respectively. Suggestions are made for process improvements and improving process economics.
- Research Organization:
- Department of Agriculture, Albany, CA (USA). Western Regional Research Center
- DOE Contract Number:
- AI01-78CS40090
- OSTI ID:
- 6754208
- Report Number(s):
- DOE/CS/40090-T1; ON: DE83000103
- Country of Publication:
- United States
- Language:
- English
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Commercial scale production of alfalfa leaf protein concentrate
Wet fractionation of forage to reduce energy requirements of dehydration. Final technical report
Related Subjects
320303* -- Energy Conservation
Consumption
& Utilization-- Industrial & Agricultural Processes-- Equipment & Processes
ALFALFA
ANIMAL FEEDS
COST
DEHYDRATION
DEHYDRATORS
DESIGN
ECONOMICS
EFFICIENCY
ENERGY CONSERVATION
ENERGY CONSUMPTION
ENERGY EFFICIENCY
ENERGY RECOVERY
EVALUATION
EVAPORATORS
EXHAUST GASES
FLUIDS
FOOD
GASEOUS WASTES
GASES
HEAT RECOVERY
INDUSTRIAL PLANTS
LEGUMINOSAE
MARKETING
MODIFICATIONS
PLANTS
RECOVERY
WASTE HEAT UTILIZATION
WASTE PRODUCT UTILIZATION
WASTES